Retaining device for retaining a built-in appliance on a worktop

ABSTRACT

In order to provide a retaining device for retaining a built-in appliance, in particular a built-in sink unit, on a worktop, comprising at least one appliance-side retaining element, at least one worktop-side retaining element and at least one tensioning element for bracing the worktop-side retaining element and the appliance-side retaining element relative to one another, wherein the tensioning element comprises a threaded portion, a retaining portion and a reduced-diameter portion, which is disposed between the threaded portion and the retaining portion and the diameter of which is smaller than the diameter of the retaining portion, and wherein the appliance-side retaining element has at least one through-opening, through which in the fitted state of the retaining device the reduced-diameter portion of the tensioning element extends, that has increased stability, it is proposed that the retaining portion of the tensioning element and/or the threaded portion of the tensioning element in the fitted state of the retaining device is supported at its periphery against the appliance-side retaining element.

RELATED APPLICATION

This application is a continuation application of PCT/EP2007/000767filed Jan. 30, 2007, the entire specification of which is incorporatedherein by reference.

FIELD OF DISCLOSURE

The present invention relates to a retaining device for retaining abuilt-in appliance, in particular a built-in sink unit, on a worktop,comprising the following:

at least one appliance-side retaining element,at least one worktop-side retaining element andat least one tensioning element for bracing the worktop-side retainingelement and the appliance-side retaining element relative to oneanother,wherein the tensioning element comprises a threaded portion, a retainingportion and a reduced-diameter portion, which is disposed between thethreaded portion and the retaining portion and the diameter of which issmaller than the diameter of the retaining portion, andwherein the appliance-side retaining element has at least onethrough-opening, through which in the fitted state of the retainingdevice the reduced-diameter portion of a tensioning element extends.

BACKGROUND

Such a retaining device for retaining a built-in sink unit on a worktopis known from the Canadian patent specification No. 1 246 805.

With this known retaining device, during the operation of fitting theretaining device an end face of the retaining portion of the tensioningelement facing the reduced-diameter portion is pulled towards ahorizontally oriented support surface of the appliance-side retainingelement, with the result that the tensioning element in the fitted stateof the retaining device is supported only by means of this end face ofthe retaining portion against the appliance-side retaining element.

SUMMARY OF THE INVENTION

The underlying object of the present invention is to provide a retainingdevice for retaining a built-in appliance on a worktop of the initiallydescribed type that has increased stability.

In a retaining device having the features of the preamble of claim 1,this object is achieved according to the invention in that the retainingportion of the tensioning element and/or the threaded portion of thetensioning element in the fitted state of the retaining device issupported at its periphery against the appliance-side retaining element.

By virtue of the fact that the retaining portion and/or the threadedportion of the tensioning element in the fitted state are supported atsupport points disposed on the periphery of the retaining portion and/orof the threaded portion against the appliance-side retaining element, atilting of the tensioning element relative to the appliance-sideretaining element is effectively prevented and the stability of theretaining device in the fitted state is markedly increased compared tothe retaining device of the Canadian patent specification No. 1 246 805,in which the tensioning element in the fitted state of the retainingdevice is supported merely be means of an end face of the retainingportion against a horizontal support surface of the appliance-sideretaining element, this however not providing any adequate supportagainst a tilting movement of the tensioning element in a directiontransversely of the longitudinal axis of the tensioning element. Withthe retaining device according to the invention, on the other hand, thetensioning element is secured against a tilting movement transversely ofits longitudinal axis.

It is particularly advantageous if the tensioning element in the fittedstate of the retaining device is supported against the appliance-sideretaining element at least two support points that are mutually spacedapart along the longitudinal axis of the tensioning element.

In a preferred development of the retaining device according to theinvention it is further provided that the appliance-side retainingelement has a fastening region, with which the appliance-side retainingelement in the fitted state of the retaining device can be positionedagainst an edge region of the built-in appliance.

In contrast thereto, in the retaining device known from the Canadianpatent specification No. 1 246 805, the appliance-side retaining elementis welded to a sink side wall of a sink of the built-in sink unit. Thewelding of the appliance-side retaining element to the sink side wallproduces visible spot welds in the visible region of the sink.

If the fastening region of the appliance-side retaining element is thendisposed, not on a vertical visible surface of the built-in appliance,but instead on the edge region of the built-in appliance, the productionof visible spot welds on the vertical visible surfaces of the built-inappliance, in particular on a sink side wall, is prevented.

If the appliance-side retaining element is disposed on the edge regionof the built-in appliance, the retaining device is situated at the bestposition for pulling the outer edge of the built-in appliance with thegreatest possible application force towards the upper side of theworktop.

An effect achieved by the retaining device according to the inventionacting directly upon the edge region of the built-in appliance is thatparticularly the corners of the edge region of the built-in appliance donot protrude in an upward direction from the worktop in the fitted stateof the built-in appliance.

Especially if the built-in appliance is a built-in sink unit with a tapledge, the region of the tap ledge may also be pulled with a highapplication force towards the worktop, this being impossible if theappliance-side retaining element of the retaining device is disposed ona sink side wall.

This development of the retaining device according to the inventionoffers the further advantage that the cut-out in the worktop may followthe external contour of the built-in appliance and not the course ofcentral, vertical visible surfaces of the built-in appliance, inparticular of sink side walls of a built-in sink unit. This offersadvantages for the freedom of configuration when designing therespective built-in appliance.

In particular, given the use of a retaining device, the tap ledge of abuilt-in sink unit may be situated lower than the sink unit edge.

With such a retaining device it is possible to achieve a particularlylow gap dimension between the built-in appliance and the upper side ofthe worktop.

The edge region of the built-in appliance is stabilized particularlywell by means of such a retaining device.

The appliance-side retaining element disclosed in the Canadian patentspecification No. 1 246 805 is totally unsuitable for being disposed onthe edge region of the built-in sink unit. Furthermore, according tothis published specification the edge region of the sink unit is toremain flexible to allow the sink unit edge to be pulled towards theworktop even if the upper side of the worktop is uneven. This teachingof the Canadian patent specification No. 1 246 805 leads precisely awayfrom the solution according to the invention of disposing theappliance-side retaining element on the edge region of the built-inappliance in order to mechanically stabilize this edge region.

In a preferred development of the retaining device according to theinvention it is provided that the appliance-side retaining element inthe fitted state of the retaining device can be fastened, in particularby welding or gluing, by the fastening region to the edge region of thebuilt-in appliance.

In particular it may be provided that the appliance-side retainingelement in the fitted state of the retaining device can be positioned bythe fastening region against a portion of the edge region that isoriented substantially horizontally in the fitted state of the built-inappliance.

The through-opening of the appliance-side retaining element preferablycomprises at least one retaining portion, through which thereduced-diameter portion of the tensioning element passes in the fittedstate of the retaining device, and at least one introduction portion,through which the retaining portion of the tensioning element can beintroduced during fitting of the retaining device in order to bring thetensioning element and the appliance-side retaining element intoengagement with one another.

Such an introduction portion may be disposed in particular on a regionof the appliance-side retaining element that is oriented substantiallyvertically in the fitted state of the retaining device.

As an alternative to this, it may also be provided that the introductionportion of the through-opening is disposed on a region of theappliance-side retaining element that is oriented substantiallyhorizontally in the fitted state of the retaining device.

The retaining portion of the through-opening of the appliance-sideretaining element is disposed preferably on a region of theappliance-side retaining element that is oriented substantiallyhorizontally in the fitted state of the retaining device.

The sequence of the operation of fitting the built-in appliance on theworktop may be made particularly flexible if the introduction portion ofthe through-opening is so configured that the retaining portion of thetensioning element can be introduced through the introduction portionwhen the built-in appliance has already been inserted into a cut-out ofthe worktop.

If the area of passage of the introduction portion of thethrough-opening is larger than the cross-sectional area of the retainingportion of the tensioning element, this allows the tensioning element tobe pushed along its longitudinal axis into the introduction portion ofthe through-opening.

If the area of passage of the introduction portion of thethrough-opening is larger than the area of a longitudinal sectionthrough the retaining portion of the tensioning element along alongitudinal axis of the tensioning element, this allows the retainingportion of the tensioning element to be pushed transversely of thelongitudinal axis of the tensioning element through the introductionportion.

The retaining portion of the through-opening may in particular be soconfigured that it extends, starting from the introduction portion ofthe through-opening, in a longitudinal direction of the edge region ofthe built-in appliance.

The through-opening may in particular comprise two retaining portionsthat extend from the introduction portion of the through-opening inmutually opposite directions.

In a special development of the retaining device according to theinvention it is provided that the at least one retaining portion of thethrough-opening extends substantially parallel to a longitudinaldirection of the edge region of the built-in appliance.

As an alternative to this, it may also be provided that the at least oneretaining portion of the through-opening extends transversely of,preferably substantially perpendicularly to, a longitudinal direction ofthe edge region of the built-in appliance.

Furthermore, in a special development of the retaining device accordingto the invention it may be provided that the through-opening of theappliance-side retaining element opens out at an edge of theappliance-side retaining element.

In this case, it may in particular be provided that the through-openingcomprises a bent path that leads from an edge of the appliance-sideretaining element to a retaining portion of the through-opening, throughwhich retaining portion the reduced-diameter portion of the tensioningelement passes in the fitted state of the retaining device.

In a particularly preferred development of the retaining deviceaccording to the invention, the appliance-side retaining elementcomprises the fastening region, a retaining region, against which isdisposed a retaining portion of the through-opening, through whichretaining portion the reduced-diameter portion of the tensioning elementpasses in the fitted state of the retaining device, and a connectingregion that connects the fastening region to the retaining region,wherein the connecting region merges at folds into the fastening regionand into the retaining region.

In this case, the fastening region, the connecting region and theretaining region may together have a substantially Z-shaped crosssection.

In order to increase the rigidity of the appliance-side retainingelement, it is advantageous if the appliance-side retaining elementfurther comprises an additional bent region that merges at a furtherbend into the retaining region.

A tilting of the appliance-side retaining element relative to thebuilt-in appliance is prevented in a particularly effective manner ifthe additional bent region in the fitted state of the retaining deviceabuts a side wall of the built-in appliance.

This additional bent region may be bent from the retaining regiontowards the same side of the retaining region as the connecting region.

As an alternative to this, it may also be provided that the additionalbent region is bent from the retaining region towards the side of theretaining region remote from the connecting region.

The additional bent region may be oriented substantially perpendicularlyto the retaining region.

As an alternative to this, it may also be provided that the additionalbent region is oriented at an acute angle to the retaining region. Sucha development of the additional bent region is particularly suitable forsupporting the threaded portion of the tensioning element against theadditional bent region of the appliance-side retaining element in thefitted state of the retaining device.

If the tensioning element in the fitted state of the retaining device issupported against the additional bent region of the appliance-sideretaining element, this effectively prevents a tilting of the tensioningelement relative to the appliance-side retaining element.

A tilting of the worktop-side retaining element relative to the built-inappliance is effectively prevented if the worktop-side retaining elementin the fitted state of the retaining device is supported against thebuilt-in appliance.

In order to secure the worktop-side retaining element in its angularposition relative to the tensioning element during the bracing of theworktop-side retaining element and the appliance-side retaining elementtowards the worktop, it is advantageous if the worktop-side retainingelement is provided with at least one claw for digging into the worktop.

Claim 28 is directed to a combination of a built-in appliance, inparticular a built-in sink unit, and at least one retaining deviceaccording to the invention.

In a preferred development of such a combination, the built-in appliancetakes the form of a built-in sink unit and comprises at least one sink,wherein the edge region of the built-in sink unit projects out from thesink towards an outer edge of the built-in sink unit. The appliance-sideretaining element of the retaining device according to the invention isthen disposed on this edge region of the built-in sink unit thatprojects towards the outer edge of the built-in sink unit.

Further features and advantages of the invention are the subject matterof the following description and the graphical representation ofembodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a diagrammatic section through a sink side wall and an edgeregion of a built-in sink unit as well as through a retaining devicecomprising an appliance-side retaining element, which is fastened to theedge region of the built-in sink unit, and a worktop-side retainingelement, which has a through-opening with internal thread, into which atensioning element of the retaining device is screwed, wherein thetensioning element is not yet in engagement with the appliance-sideretaining element;

FIG. 2 a diagrammatic sectional view corresponding to FIG. 1 of theretaining device after a retaining portion of the tensioning element hasbeen introduced through an introduction portion of a through-opening ofthe appliance-side retaining element;

FIG. 3 a diagrammatic sectional view corresponding to FIG. 2 of theretaining device after the built-in sink unit has been inserted into acut-out of a worktop;

FIG. 4 a diagrammatic sectional view corresponding to FIG. 3 of theretaining device after the worktop-side retaining element has beenrotated from the insertion position shown in FIG. 3 through an angle of90° into the support position shown in FIG. 4;

FIG. 5 a diagrammatic perspective view of the edge region of thebuilt-in sink unit having the retaining device of FIGS. 1 to 4 disposedthereon;

FIG. 6 a diagrammatic exterior view of the appliance-side retainingelement of FIGS. 1 to 5, viewed in the direction of the arrow 6 in FIG.7;

FIG. 7 a diagrammatic side view of the appliance-side retaining elementof FIGS. 1 to 5;

FIG. 8 a diagrammatic top view of the appliance-side retaining elementof FIG. 7, viewed in the direction of the arrow 8 in FIG. 7;

FIG. 9 a diagrammatic side view of the tensioning element of theretaining device of FIGS. 1 to 5;

FIG. 10 a diagrammatic side view of the worktop-side retaining elementof the retaining device of FIGS. 1 to 5;

FIG. 11 a diagrammatic front view of the worktop-side retaining elementof FIG. 10, viewed in the direction of the arrow 11 in FIG. 10;

FIG. 12 a diagrammatic top view of the worktop-side retaining element ofFIG. 10, viewed in the direction of the arrow 12 in FIG. 10;

FIG. 13 a diagrammatic section through a sink side wall and an edgeregion of a built-in sink unit as well as a second embodiment of aretaining device, in which the worktop-side retaining element liesagainst the sink side wall in the fitted state of the retaining device;

FIG. 14 a diagrammatic section through a sink side wall and an edgeregion of a built-in sink unit as well as a third embodiment of aretaining device, the appliance-side retaining element of which has anadditional, upwardly bent region;

FIG. 15 a diagrammatic exterior view of the appliance-side retainingelement of FIG. 14, viewed in the direction of the arrow 15 in FIG. 16;

FIG. 16 a diagrammatic side view of the appliance-side retaining elementof FIG. 14;

FIG. 17 a diagrammatic top view of the appliance-side retaining elementof FIG. 16, viewed in the direction of the arrow 17 in FIG. 16;

FIG. 18 a diagrammatic section through a sink side wall and an edgeregion of a built-in sink unit as well as a fourth embodiment of aretaining device, the appliance-side retaining element of which has anadditional, upwardly bent region that lies against the outside of thesink side wall in the fitted state of the retaining device;

FIG. 19 a diagrammatic section through a sink side wall and an edgeregion of a built-in sink unit as well as a fifth embodiment of aretaining device, the appliance-side retaining element of which has athrough-opening with an introduction portion, which is so configuredthat the retaining portion of the tensioning element, when the built-insink unit has already been inserted into the cut-out of the worktop, maybe moved in substantially horizontal direction through the introductionportion, wherein the tensioning element and the appliance-side retainingelement in the initial state shown in FIG. 19 are not yet in engagementwith one another;

FIG. 20 a sectional view corresponding to FIG. 19 of the retainingdevice after the retaining portion of the tensioning element has beenmoved through the introduction portion of the through-opening;

FIG. 21 a sectional view corresponding to FIG. 20 of the retainingdevice after the retaining portion of the tensioning element has beenbrought into abutment with a retaining region of the appliance-sideretaining element;

FIG. 22 a diagrammatic exterior view of the appliance-side retainingelement of the retaining device of FIGS. 19 to 21, viewed in thedirection of the arrow 22 in FIG. 23;

FIG. 23 a diagrammatic side view of the appliance-side retaining elementof the retaining device of FIGS. 19 to 21;

FIG. 24 a diagrammatic top view of the appliance-side retaining elementof FIG. 23, viewed in the direction of the arrow 24 in FIG. 23;

FIG. 25 a diagrammatic exterior view of a sink side wall and an edgeregion of a built-in sink unit as well as a sixth embodiment of aretaining device, the appliance-side retaining element of which has forthe tensioning element a through-opening extending in the longitudinaldirection of the edge region of the built-in sink unit, in an initialstate in which the appliance-side retaining element and the tensioningelement are not yet in engagement with one another;

FIG. 26 a diagrammatic section through the through-opening of theappliance-side retaining element of the retaining device of FIG. 25;

FIG. 27 a diagrammatic exterior view corresponding to FIG. 25 of theretaining device after the retaining portion of the tensioning elementhas been introduced through the introduction portion of thethrough-opening;

FIG. 28 a diagrammatic section through the through-opening of theappliance-side retaining element of the retaining device of FIG. 27;

FIG. 29 a diagrammatic exterior view corresponding to FIG. 27 of theretaining device after the reduced-diameter portion of the tensioningelement has been displaced into a retaining portion of thethrough-opening of the appliance-side retaining element;

FIG. 30 a diagrammatic section through the through-opening of theappliance-side retaining element of the retaining device of FIG. 29;

FIG. 31 a diagrammatic exterior view of the appliance-side retainingelement of the retaining device of FIGS. 25 to 30, viewed in thedirection of the arrow 31 in FIG. 32;

FIG. 32 a diagrammatic side view of the appliance-side retaining elementof the retaining device of FIGS. 25 to 30;

FIG. 33 a diagrammatic top view of the appliance-side retaining elementof FIG. 32, viewed in the direction of the arrow 33 in FIG. 32;

FIG. 34 a diagrammatic section through a sink side wall and an edgeregion of a built-in sink unit as well as a seventh embodiment of aretaining device, the appliance-side retaining element of which has anadditional, downwardly bent region;

FIG. 35 a diagrammatic exterior view of the appliance-side retainingelement of the retaining device of FIG. 34, viewed in the direction ofthe arrow 35 in FIG. 36;

FIG. 36 a diagrammatic side view of the appliance-side retaining elementof the retaining device of FIG. 34;

FIG. 37 a diagrammatic top view of the appliance-side retaining elementof FIG. 36, viewed in the direction of the arrow 37 in FIG. 36;

FIG. 38 a diagrammatic section through an eighth embodiment of aretaining device, the appliance-side retaining element of which has anangled through-opening for the tensioning element comprising anintroduction slot, a retaining portion and a connecting channel betweenthe introduction slot and the retaining portion as well as an obliquelydownwardly bent region, in an initial state, in which the tensioningelement passes through the introduction slot of the through-opening ofthe appliance-side retaining element;

FIG. 39 a diagrammatic top view of the retaining device of FIG. 38;

FIG. 40 a diagrammatic sectional view corresponding to FIG. 38 of theretaining device after the reduced-diameter portion of the tensioningelement has been displaced from the introduction slot to the oppositeend of the connecting channel;

FIG. 41 a diagrammatic top view of the retaining device of FIG. 40;

FIG. 42 a diagrammatic sectional view corresponding to FIG. 40 of theretaining device after the tensioning element has been pivoted into avertical tensioning position;

FIG. 43 a diagrammatic top view of the retaining device of FIG. 42;

FIG. 44 a diagrammatic exterior view of the appliance-side retainingelement of the retaining device of FIGS. 38 to 43, viewed in thedirection of the arrow 44 in FIG. 45;

FIG. 45 a diagrammatic side view of the appliance-side retaining elementof the retaining device of FIGS. 38 to 43;

FIG. 46 a diagrammatic top view of the appliance-side retaining elementof FIG. 45, viewed in the direction of the arrow 46 in FIG. 45; and

FIG. 47 a diagrammatic perspective view of the retaining device of FIGS.38 to 45 after the tensioning element has been moved into the verticaltensioning position.

Identical or functionally equivalent elements are denoted in all of thefigures by the same reference characters.

DETAILED DESCRIPTION OF THE INVENTION

A built-in appliance for example in the form of a built-in sink unit100, a detail of which is shown in FIGS. 1 to 5, comprises acircumferential edge region 102 having an, in the fitted state of thebuilt-in sink unit 100, substantially horizontally oriented,substantially flat horizontal edge portion 104 that at its outer edgemerges into an outer edge portion 106, which extends obliquely relativeto the horizontal and terminates at an outer edge 108 of the built-insink unit 100, and at its inner edge merges into a (viewed from abovethe built-in sink unit 100) concavely curved inner edge portion 110,which adjoins a substantially horizontal sink unit surface 112. Asubstantially horizontally oriented circumferential upper edge 114 of asink 116 of the built-in sink unit 100 is fastened to the underside ofthe sink unit surface 112 and projects out from a sink side wall 118 ofthe sink 116.

In the embodiment shown here, the sink 116 is manufactured separatelyfrom the edge region 102 of the built-in sink unit 100 and fastened—forexample by welding—to the edge region 102. As an alternative to this, itwould however also be possible to manufacture the sink 116 integrallywith the edge region 102 of the built-in sink unit 100.

The sink unit 100 may in principle be manufactured from any desiredmaterial.

Preferably, the sink unit 100 is formed from a metal material,preferably from a steel material, in particular from a nickel chromiumsteel.

As may be seen from FIG. 4, the built-in sink unit 100 in the fittedstate is inserted from above into a cut-out 120 in a worktop 122 that isadapted to the external contour of the built-in sink unit 100, whereinthe edge region 102 of the built-in sink unit 100, via a sealing element124, for example a microcellular rubber seal glued onto the underside ofthe edge region 102, abuts an upper side 126 of the worktop 122 in asubstantially liquid-proof manner.

The worktop 122 is carried for example by side walls 128 of a kitchenbase unit.

In order to fasten the built-in sink unit 100 to the worktop 122 in sucha way that it is no longer removable in an upward direction from thecut-out 120, on the edge region 102 of the built-in sink unit 100 aplurality of appliance-side retaining elements 132 extending in eachcase in the longitudinal direction 130 of the edge region 102 arefastened and interact with in each case one or more worktop-sideretaining elements 134 and in each case one or more tensioning elements136 in such a way that the built-in sink unit 100 is braced towards theworktop 122.

An appliance-side retaining element 132 therefore together with one ormore worktop-side retaining elements 134 and one or more tensioningelements 136 forms a retaining device 138 for retaining the built-insink unit 100 on the worktop 122.

As may be seen from FIG. 5, it may for example be provided that in eachcase one appliance-side retaining element 132 in the form of a retainingstrip extends substantially over in each case one longitudinal side ofthe built-in sink unit 100.

It is however also possible for a plurality of appliance-side retainingelements 132 that are mutually spaced apart in the longitudinaldirection 130 of the edge region 102 of the built-in sink unit 100 to beprovided along each longitudinal side of the built-in sink unit 100.

As may best be seen from FIGS. 6 to 8, each of the appliance-sideretaining elements 132 has a substantially constant cross section alongthe longitudinal direction 130 and comprises in each case a fasteningregion 140 that in the fitted state of the retaining device 138 ishorizontally oriented, a connecting region 144 that along a first bend142 adjoins the fastening region 140 and extends vertically downwardsfrom the fastening region 140, as well as a retaining region 148 thatalong a second bend 146 adjoins the connecting region 144 and extendsfrom the connecting region 144 in a horizontally inward direction (i.e.towards the sink 116 of the built-in sink unit 100).

The fastening region 140 and the retaining region 148 therefore projectin different directions from the connecting region 144.

The appliance-side retaining element 132 lies with the fastening region140 against the underside of the horizontal edge portion 104 of the edgeregion 102 of the built-in sink unit 100 and is fastened—for example bywelding—to the edge region 102 of the built-in sink unit 100.

In order to be able to bring the appliance-side retaining element 132into engagement with the tensioning element 136, the appliance-sideretaining element 132 is provided with at least one through-opening 150for the tensioning element 136.

As may best be seen from FIG. 9, the tensioning element 136 takes theform of a fastening screw and comprises a screw head 152, a threadedportion 154 having an outside diameter D, a reduced-diameter portion156, which adjoins the threaded portion 154 and the smallest outsidediameter d of which is smaller than the outside diameter D of thethreaded portion 154, and a retaining portion 158, which adjoins thereduced-diameter portion 156 and has a larger outside diameter than thereduced-diameter portion 156 and in particular may have the same outsidediameter D as the threaded portion 154.

The retaining portion 158 may also, like the threaded portion 154, beprovided with an external thread.

The external thread of the threaded portion 154 and of the retainingportion 158 may in particular take the form of a left-hand thread.

The reduced-diameter portion 156 takes the form of a relief groovebetween the threaded portion 154 and the retaining portion 158 andpreferably has a curved outer surface in order to avoid notch effects.

The screw head 152 preferably takes the form of a Robertson screw head,i.e. a screw head having a central recess 160 with a substantiallysquare cross section for receiving the tip of a Robertson screwdriver.

The external contour of the screw head 152 may for example be of ahexagonal design in order to allow the tensioning element 136 to berotated by means of a spanner.

The through-opening 150 of the appliance-side retaining element 132 isof a keyhole-shaped design and comprises an approximately circularintroduction portion 162, which is disposed on the connecting region 144and the diameter of which exceeds the outside diameter D of theretaining portion 158, and a retaining portion 164, which extends fromthe bottom edge of the introduction portion 162 into the retainingregion 148 of the appliance-side retaining element 132 and the width bof which (i.e. the extent thereof in the longitudinal direction 130 ofthe edge region 102 of the built-in sink unit 100) is smaller than theoutside diameter D of the retaining portion 158 of the tensioningelement 136 and slightly larger than the smallest outside diameter d ofthe reduced-diameter portion 156.

The tensioning element 136 may therefore be introduced by the retainingportion 158 through the introduction portion 162 of the through-opening150, until the reduced-diameter portion 156 passes into the region ofthe through-opening 150, and is then moved in such a way relative to theappliance-side retaining element 132 that the reduced-diameter portion156 passes into the retaining portion 164 of the through-opening 150 andthe retaining portion 158 of the tensioning element 136 is supportedagainst the region of the appliance-side retaining element 132 thatsurrounds the retaining portion 164 of the through-opening 150.

The worktop-side retaining element 134 is shown individually in FIGS. 10to 12 and in this embodiment takes the form of a retaining bracketcomprising a coupling region 166 and a support region 168 extending atan obtuse angle to the coupling region 166.

The support region 168 is provided at its upper end with twosharp-spiked claws 170 that are able to dig into the underside 172 ofthe worktop 122.

The coupling region 166 of the worktop-side retaining element 134 isprovided with a tapped hole 174, the internal thread of which is of acomplementary design to the external thread of the tensioning element136, so that the tensioning element 136 may be screwed by its threadedportion 154 into the tapped hole 174 of the worktop-side retainingelement 134, in the manner shown in FIG. 1.

The operation of fitting the built-in sink unit 100 on the worktop 122is described below with reference to FIGS. 1 to 4.

In the initial state shown in FIG. 1, the built-in sink unit 100 has notyet been inserted into the cut-out 120 of the worktop 122. In thisstate, the tensioning element 136 with the worktop-side retainingelement 134 disposed thereon is inserted in such a way into theintroduction portion 162 of the through-opening 150 of theappliance-side retaining element 132 that the longitudinal axis 176 ofthe tensioning element 136 extends at an angle β of ca. 0° to ca. 30° tothe upper side of the retaining region 148 and to the upper side of thehorizontal edge portion 104 of the built-in sink unit 100.

In this case, the tensioning element 136 is inserted far enough throughthe introduction portion 162 for the reduced-diameter portion 156 of thetensioning element 136 to be situated in the introduction portion 162(see FIG. 2).

The tensioning element 136 is then pivoted into the vertical, with theresult that the reduced-diameter portion 156 moves from the introductionportion 162 of the through-opening 150 into the retaining portion 164thereof (see FIG. 3). In this position, the tensioning element 136 isprevented from moving out of the through-opening 150 of theappliance-side retaining element 132 because the retaining portion 158of the tensioning element 136 has the diameter D, which is larger thanthe width b of the retaining portion 158 of the through-opening 150.

The worktop-side retaining element 134 is moreover rotated in such a waythat the coupling region 166 and the support region 168 are alignedsubstantially parallel to the longitudinal direction 130 of the edgeregion 102 of the built-in sink unit 100 and hence also substantiallyparallel to the boundary wall 178 of the cut-out 120 in the worktop 122.

In this position, the built-in sink unit 100 with the retaining devices138 disposed thereon may be inserted from above into the cut-out 120 ofthe worktop 122, thereby achieving the state shown in FIG. 3.

The worktop-side retaining element 134 is then rotated (through an angleof ca. 90°) from the insertion position shown in FIG. 3 into the supportposition shown in FIG. 4, thereby allowing the claws 170 of the supportregion 168 to dig into the underside 172 of the worktop 122.

The tensioning element 136 is then rotated by means of a suitable tool,for example a Robertson screwdriver, about its longitudinal axis 176 insuch a way that the worktop-side retaining element 134 in engagementwith the threaded portion 154 and the appliance-side retaining element132 in engagement with the reduced-diameter portion 156 are movedtowards one another and hence braced towards one another and towards theworktop 122.

During the bracing operation the retaining portion 158 of the tensioningelement 136 lies with its periphery against a first support point 180 onthe connecting region 144 of the appliance-side retaining element 132,and the reduced-diameter portion 156 lies with its periphery against asecond support point 182 on the edge of the retaining portion 164 of thethrough-opening 150 of the appliance-side retaining element 132, withthe result that the tensioning element 136 is supported against theappliance-side retaining element 132 at two, in relation to thelongitudinal axis 176 of the tensioning element 136, diametricallyopposite support points 180, 182 and is therefore prevented from tiltingrelative to the appliance-side retaining element 132.

After the appliance-side retaining element 132 and hence also the edgeregion 102 of the built-in sink unit 100 have been pulled towards theupper side 126 of the worktop 122, the fitting of the built-in sink unit100 on the worktop 122 is complete.

Disassembly of the built-in sink unit 100 is effected by reversing thepreviously described operations.

The tensioning element 136 is formed preferably from a metal material,in particular from a steel material.

The appliance-side retaining element 132 and the worktop-side retainingelement 134 are likewise formed preferably from a metal material, inparticular from a sheet steel, by means of cutting and foldingoperations.

A second embodiment of a retaining device 138 shown in FIG. 13 differsfrom the previously described first embodiment merely in that thecoupling region 166 of the worktop-side retaining element 134 is of sucha length that it is supported, in the fitted state of the retainingdevice 138 shown in FIG. 13, against the outside of the sink side wall118 of the built-in sink unit 100. This prevents a tilting of theworktop-side retaining element 134 and of the tensioning element 136relative to the built-in sink unit 100 and hence relative to theappliance-side retaining element 132.

Otherwise the second embodiment of a retaining device 138 shown in FIG.13 is identical in construction and function to the first embodimentshown in FIGS. 1 to 12, to the previous description of which referenceis made in this respect.

A third embodiment of a retaining device 138 shown in FIGS. 14 to 17differs from the previously described first embodiment in that theappliance-side retaining element 132 in addition to the connectingregion 144 and the retaining region 148 has an additional bent region184, which along a third bend 186 adjoins the inner edge of theretaining region 148 remote from the connecting region 144 and extendsin a substantially vertically upward direction from the retaining region148, substantially parallel to the connecting region 144.

By virtue of the additional bend an additional stiffening of theappliance-side retaining element 132 is simultaneously achieved.

Otherwise the third embodiment of a retaining device 138 shown in FIGS.14 to 17 is identical in construction and function to the firstembodiment shown in FIGS. 1 to 12, to the previous description of whichreference is made in this respect.

A fourth embodiment of a retaining device 138 shown in FIG. 18 differsfrom the third embodiment shown in FIGS. 14 to 17 merely in that thewidth of the retaining region 148, i.e. the extent thereof at rightangles to the longitudinal direction 130 of the edge region 102 of thebuilt-in sink unit 100, is increased to such an extent that theadditional bent region 184 in the fitted state of the retaining device138 lies against the outside of the sink side wall 118 of the built-insink unit 100, with the result that the appliance-side retaining element132 is supported against the sink side wall 118, thereby preventing atilting of the appliance-side retaining element 132 and hence of theentire retaining device 138 relative to the built-in sink unit 100.

Otherwise the fourth embodiment shown in FIG. 18 is identical inconstruction and function to the third embodiment shown in FIGS. 14 to17, to the previous description of which reference is made in thisrespect.

A fifth embodiment of a retaining device 138 shown in FIGS. 19 to 24differs from the first embodiment shown in FIGS. 1 to 12 in thedevelopment of the introduction portion 162 of the through-opening 150of the appliance-side retaining element 132.

As may best be seen from FIG. 22, in this embodiment this introductionportion 162 is not of a circular design but substantially of arectangular design, wherein the area of passage of this rectangularintroduction portion 162 is slightly larger than the area of alongitudinal section along the longitudinal axis 176 of the tensioningelement 136 through the retaining portion 158 of the tensioning element136.

As is shown in FIGS. 19 to 21, the retaining portion 158 may thereforebe moved laterally, in substantially horizontal direction, through theintroduction portion 162 in order to suspend the tensioning element 136from the appliance-side retaining element 132.

FIG. 19 shows the initial state before the retaining portion 158 of thetensioning element 136 passes through the introduction portion 162.

FIG. 20 shows the state after the retaining portion 158 of thetensioning element 136 has been moved through the introduction portion162. In this state, the reduced-diameter portion 156 of the tensioningelement 136 is in engagement with the retaining portion 164 of theappliance-side retaining element.

FIG. 21 shows the final state of assembly of this fifth embodiment ofthe retaining device 138, in which the retaining portion 158 as a resultof the bracing of the appliance-side retaining element 132 and of theworktop-side retaining element 134 has been pulled down towards theretaining region 148 of the appliance-side retaining element 132. Inthis position, the retaining portion 158 lies with its periphery againsta first support point 180 on the connecting region 144 of theappliance-side retaining element 132, while at the diametricallyopposite side of the tensioning element 136 the reduced-diameter portion156 lies with its periphery against a second support point 182 on theedge of the retaining portion 164 of the through-opening 150 of theappliance-side retaining element 132. The tensioning element 136 istherefore supported at two mutually diametrically opposite supportpoints 180, 182 against the appliance-side retaining element 132,thereby preventing a tilting of the tensioning element 136 relative tothe appliance-side retaining element 132.

The length of the reduced-diameter portion 156 in this embodiment isgreater than in the previously described embodiments.

This embodiment of the retaining device 138, in which the tensioningelement 136 is not inserted into the through-opening 150 of theappliance-side retaining element 132 in a horizontal orientation or anorientation only slightly inclined relative to the horizontal but isfitted from below into the gap between the appliance-side retainingelement 132, on the one hand, and the boundary wall 178 of the worktop122, on the other hand, before then passing laterally through thethrough-opening 150 of the appliance-side retaining element, offers theadvantage that the tensioning element 136 does not have to be alreadysuspended from the appliance-side retaining element 132 prior toinsertion of the built-in sink unit 100 into the cut-out 120 of theworktop 122, rather the suspension of the tensioning element 136 fromthe appliance-side retaining element 132 may alternatively be effectedfrom underneath the worktop 122 after insertion of the built-in sinkunit 100 into the cut-out 120 of the worktop 122.

Otherwise the fifth embodiment of a retaining device 138 shown in FIGS.19 to 24 is identical in construction and function to the firstembodiment shown in FIGS. 1 to 12, to the previous description of whichreference is made in this respect.

A sixth embodiment of a retaining device 138 shown in FIGS. 25 to 33differs from the previously described fifth embodiment in that theintroduction portion 162 of the through-opening 150 in theappliance-side retaining element 132 is disposed, not in the connectingregion 144 of the appliance-side retaining element 132, but in theretaining region 148 of the appliance-side retaining element 132.

As may best be seen from FIG. 33, the through-opening 150 of theappliance-side retaining element 132 in this embodiment comprises acircular introduction portion 162, the diameter of which is slightlylarger than the outside diameter D of the retaining portion 158 of thetensioning element 136, as well as two narrower retaining portions 164that extend away from the introduction portion 162 in mutually oppositedirections, substantially parallel to the longitudinal direction 130 ofthe edge region 102 of the built-in sink unit 100. The width b of bothretaining portions 164, i.e. the extent thereof at right angles to thelongitudinal direction 130 of the edge region 102, is in this casesmaller than the outside diameter D of the retaining portion 158 of thetensioning element 136 but slightly larger than the smallest diameter dof the reduced-diameter portion 156 of the tensioning element 136, withthe result that the retaining portion 158 of the tensioning element 136may be pushed from below in vertical direction through the introductionportion 162 until the reduced-diameter portion 156 is situated in theintroduction portion 162 (see FIGS. 25 to 28).

By displacing the tensioning element 136 in horizontal direction, thereduced-diameter portion 156 may then be moved into one of the tworetaining portions 164 (see FIGS. 29 and 30). In this position thetensioning element 136 is secured against a moving of the retainingportion 158 out through the through-opening 150 of the appliance-sideretaining element 132 because the retaining portion 158 as a result ofthe tightening of the tensioning element 136 is pulled towards theregions of the retaining region 148 of the appliance-side retainingelement 132 that surround the retaining portion 164 of thethrough-opening 150 and is held fast by these regions.

The through-opening 150 of the appliance-side retaining element 132 inthis embodiment therefore has the shape of an elongate hole that extendsin the longitudinal direction 130 of the edge region 102 of the built-insink unit 100.

In this embodiment of the retaining device 138 too, the tensioningelement 136 may be suspended from the appliance-side retaining element132 after the built-in sink unit 100 has already been inserted into thecut-out 120 of the worktop 122.

Otherwise the sixth embodiment of a retaining device 138 shown in FIGS.25 to 33 is identical in construction and function to the fifthembodiment shown in FIGS. 19 to 24, to the previous description of whichreference is made in this respect.

A seventh embodiment of a retaining device 138 shown in FIGS. 34 to 37differs from the third embodiment shown in FIGS. 14 to 17 in that theadditional bent region 184 extends, not upwards from the retainingregion 148, but rather downwards from the retaining region 148,substantially parallel to the connecting region 144.

In this embodiment, in the fitted state of the retaining device 138 theretaining portion 158 of the tensioning element 136 lies with itsperiphery against a first support point 180 on the connecting region 144of the appliance-side retaining element 132, while the threaded portion154 of the tensioning element 136 lies with its periphery against asecond support point 182 on the additional bent region 184 of theappliance-side retaining element 132.

In the fitted state of the retaining device 138, the tensioning element136 is therefore supported against the appliance-side retaining element132 at two support points 180, 182, which lie in relation to thelongitudinal axis 176 of the tensioning element 136 diametricallyopposite one another and are markedly spaced apart from one another invertical direction, thereby achieving particularly good support of thetensioning element 136 and in a particularly effective manner preventinga tilting of the tensioning element 136 relative to the appliance-sideretaining element 132.

By virtue of the additional bend on the appliance-side retaining element132, the appliance-side retaining element 132 is moreover additionallystiffened.

Otherwise the seventh embodiment of a retaining device 138 shown inFIGS. 34 to 37 is identical in construction and function to the thirdembodiment shown in FIGS. 14 to 17, to the previous description of whichreference is made in this respect.

An eighth embodiment of a retaining device 138 shown in FIGS. 38 to 47differs from the seventh embodiment shown in FIGS. 34 to 37 in that theintroduction portion 162 of the through-opening 150 of theappliance-side retaining element 132 is disposed, not in the connectingregion 144, but partly on the additional bent region 184 and partly onthe retaining region 148 of the appliance-side retaining element 132.

As may best be seen from FIG. 47, the introduction portion 162 in thisembodiment takes the form of an introduction slot 190, which opens outat the bottom edge 188 of the additional bent region 184 and the width Bof which (i.e. the extent thereof in the longitudinal direction 130 ofthe edge region 102 of the built-in sink unit 100) is at least slightlygreater than the outside diameter D of the retaining portion 158 and ofthe threaded portion 154 of the tensioning element 136. The introductionslot 190 extends from the bottom edge 188 of the additional bent region184 right into the retaining region 148 of the appliance-side retainingelement 132. The retaining portion 164 of the through-opening 150extends substantially parallel to the introduction slot 190, i.e.transversely of the longitudinal direction 130 of the edge region 102 ofthe built-in sink unit 100, through the retaining region 148 and isspaced apart from the introduction slot 190 in the longitudinaldirection 130.

The retaining portion 164, the width b of which is smaller than theoutside diameter D of the retaining portion 158 of the tensioningelement 136, is connected to the introduction slot 190 by a connectingchannel 192 that extends substantially parallel to the longitudinaldirection 130 of the edge region 102 of the built-in sink unit 100.

The width of this connecting channel 192, i.e. the extent thereof atright angles to the longitudinal direction 130, is likewise smaller thanthe outside diameter D of the retaining portion 158 of the tensioningelement 136.

In this embodiment, moreover, the additional bent region 184 is notoriented substantially vertically but forms with the vertical an acuteangle and in the fitted state of the retaining device 138 is inclinedtowards the tensioning element 136.

In this embodiment the procedure for suspending the tensioning element136 from the appliance-side retaining element 132 is as described belowwith reference to FIGS. 38 to 43.

First the tensioning element 136 is inserted obliquely relative to thehorizontal and obliquely relative to the vertical into the introductionslot 190 until the retaining portion 158 of the tensioning element 136has passed through the introduction slot 190 and the reduced-diameterportion 156 comes to lie in the region of the introduction slot 190 (seeFIGS. 38 and 39).

Then the tensioning element 136 is displaced parallel to thelongitudinal direction 130 of the edge region 102 of the built-in sinkunit 100, wherein the reduced-diameter portion 156 of the tensioningelement 136 moves from the introduction slot 190 to the opposite end ofthe connecting channel (see FIGS. 40 and 41).

Finally the tensioning element 136 is pivoted from the oblique positioninto the vertical position in order to achieve the tensioning positionshown in FIGS. 42 and 43, in which the reduced-diameter portion 156 ofthe tensioning element 136 penetrates the retaining portion 164 of thethrough-opening 150 in the appliance-side retaining element 132.

In this position, the retaining portion 158 of the tensioning element136 moreover lies with its periphery against a first support point 180on the connecting region 144 of the appliance-side retaining element132, while the threaded portion 154 of the tensioning element 136 lieswith its periphery against a second support point 182 on the bottom edge188 of the additional bent region 184.

Thus, in the fitted position of the retaining device 138 the tensioningelement 135 is supported by the appliance-side retaining element 132 attwo support points 180, 182 that lie in relation to the longitudinalaxis 176 of the tensioning element 136 diametrically opposite oneanother and are markedly spaced apart vertically from one another,thereby in a particularly effective manner preventing a tilting of thetensioning element 136 relative to the appliance-side retaining element132.

Otherwise the eighth embodiment of a retaining device 138 shown in FIGS.38 to 47 is identical in construction and function to the seventhembodiment shown in FIGS. 34 to 37, to the previous description of whichreference is made in this respect.

1. Retaining device for retaining a built-in appliance, in particular abuilt-in sink unit, on a worktop, comprising at least one appliance-sideretaining element, at least one worktop-side retaining element and atleast one tensioning element for bracing the worktop-side retainingelement and the appliance-side retaining element relative to oneanother, wherein the tensioning element comprises a threaded portion, aretaining portion and a reduced-diameter portion, which is disposedbetween the threaded portion and the retaining portion and the diameterof which is smaller than the diameter of the retaining portion, andwherein the appliance-side retaining element has at least onethrough-opening, through which in the fitted state of the retainingdevice the reduced-diameter portion of a tensioning element extends,wherein the retaining portion of the tensioning element and/or thethreaded portion of the tensioning element in the fitted state of theretaining device is supported at its periphery against theappliance-side retaining element.
 2. Retaining device according to claim1, wherein the tensioning element in the fitted state of the retainingdevice is supported against the appliance-side retaining element atleast two support points that are mutually spaced apart along thelongitudinal axis of the tensioning element.
 3. Retaining deviceaccording to claim 1, wherein the appliance-side retaining element has afastening region, by which the appliance-side retaining element in thefitted state of the retaining device can be positioned against an edgeregion of the built-in appliance.
 4. Retaining device according to claim3, wherein the appliance-side retaining element in the fitted state ofthe retaining device can be positioned by the fastening region against aportion of the edge region that is oriented substantially horizontallyin the fitted state of the built-in appliance.
 5. Retaining deviceaccording to claim 3, wherein the through-opening comprises at least oneretaining portion, through which the reduced-diameter portion of thetensioning element passes in the fitted state of the retaining device,and at least one introduction portion, through which the retainingportion of the tensioning element can be introduced during fitting ofthe retaining device in order to bring the tensioning element and theappliance-side retaining element into engagement with one another. 6.Retaining device according to claim 5, wherein the introduction portionis disposed on a region of the appliance-side retaining element that isoriented substantially vertically in the fitted state of the retainingdevice.
 7. Retaining device according to claim 5, wherein theintroduction portion of the through-opening is disposed on a region ofthe appliance-side retaining element that is oriented substantiallyhorizontally in the fitted state of the retaining device.
 8. Retainingdevice according to claim 5, wherein the retaining portion of thethrough-opening is disposed on a region of the appliance-side retainingelement that is oriented substantially horizontally in the fitted stateof the retaining device.
 9. Retaining device according to claim 5,wherein the introduction portion of the through-opening is so configuredthat the retaining portion of the tensioning element can be introducedthrough the introduction portion when the built-in appliance has alreadybeen inserted into a cut-out of the worktop.
 10. Retaining deviceaccording to claim 5, wherein the area of passage of the introductionportion of the through-opening is larger than the cross-sectional areaof the retaining portion of the tensioning element.
 11. Retaining deviceaccording to claim 5, wherein the area of passage of the introductionportion of the through-opening is larger than the area of a longitudinalsection through the retaining portion of the tensioning element along alongitudinal axis of the tensioning element.
 12. Retaining deviceaccording to claim 5, wherein the retaining portion of thethrough-opening extends, starting from the introduction portion of thethrough-opening, in a longitudinal direction of the edge region of thebuilt-in appliance.
 13. Retaining device according to claim 5, whereinthe through-opening comprises two retaining portions that extend fromthe introduction portion of the through-opening in mutually oppositedirections.
 14. Retaining device according to claim 5, wherein the atleast one retaining portion of the through-opening extends substantiallyparallel to a longitudinal direction of the edge region of the built-inappliance.
 15. Retaining device according to claim 5, wherein the atleast one retaining portion of the through-opening extends transverselyof, preferably substantially perpendicularly to, a longitudinaldirection of the edge region of the built-in appliance.
 16. Retainingdevice according to claim 1, wherein the through-opening opens out at anedge of the appliance-side retaining element.
 17. Retaining deviceaccording to claim 16, wherein the through-opening comprises a bent paththat leads from an edge of the appliance-side retaining element to aretaining portion of the through-opening, through which retainingportion the reduced-diameter portion of the tensioning element passes inthe fitted state of the retaining device.
 18. Retaining device accordingto claim 1, wherein the appliance-side retaining element comprises thefastening region, a retaining region, against which is disposed aretaining portion of the through-opening, through which retainingportion the reduced-diameter portion of the tensioning element passes inthe fitted state of the retaining device, and a connecting region thatconnects the fastening region to the retaining region, wherein theconnecting region merges at folds into the fastening region and into theretaining region.
 19. Retaining device according to claim 18, whereinthe appliance-side retaining element further comprises an additionalbent region that merges at a further bend into the retaining region. 20.Retaining device according to claim 19, wherein the additional bentregion lies against a side wall of the built-in appliance in the fittedstate of the retaining device.
 21. Retaining device according to claim19, wherein the additional bent region is bent from the retaining regiontowards the same side of the retaining region as the connecting region.22. Retaining device according to claim 19, wherein the additional bentregion is bent from the retaining region towards the side of theretaining region remote from the connecting region.
 23. Retaining deviceaccording to claim 19, wherein the additional bent region is orientedsubstantially perpendicularly to the retaining region.
 24. Retainingdevice according to claim 19, wherein the additional bent region isoriented at an acute angle to the retaining region.
 25. Retaining deviceaccording to claim 19, wherein the tensioning element in the fittedstate of the retaining device is supported against the additional bentregion of the appliance-side retaining element.
 26. Retaining deviceaccording to claim 1, wherein the worktop-side retaining element in thefitted state of the retaining device is supported against the built-inappliance.
 27. Retaining device according to claim 1, wherein theworktop-side retaining element is provided with at least one claw fordigging into the worktop.
 28. Combination of a built-in appliance, inparticular a built-in sink unit, and at least one retaining deviceaccording to claim
 1. 29. Combination according to claim 28, wherein thebuilt-in appliance takes the form of a built-in sink unit and comprisesat least one sink, wherein an edge region of the built-in sink unitprojects out from the sink towards an outer edge of the built-in sinkunit.